Acoustic device for localized contactless measurement of elastic and dissipative non-linearities and viscoelasticity

A localized and contactless acoustic measuring device to measure elastic and dissipative non-linearities and viscoelasticity of a sample, the device comprising:

• a tank operably taking up the sample;
• an emitter of a low-frequency acoustic wave capable of creating a periodic low-frequency variation of a hydrostatic pressure in the sample;
• a measurer operably measuring the variation of the hydrostatic pressure due to the low-frequency acoustic wave generated by the emitter;
• a generator of high-frequency ultrasound pulses;
• a receiver arranged vis-à-vis the generator such that the high-frequency ultrasound pulses having passed through the sample are received and measured by the receiver;
• a synchronization equipment to generate a synchronization signal to synchronize the measurements of the high-frequency ultrasound pulses and the variation of the hydrostatic pressure;
• and
• an analysis unit comprising a calculation module to calculate modulations of time of flight and of amplitude of the ultrasound pulses caused by passage of the low-frequency acoustic wave in the sample to quantify the elastic and dissipative non-linearities and the viscoelasticity of the sample.